Conventionally, a parts-packaging substrate a paper phenol substrate, a coppered laminate resin substrate such as paper phenol substrate and glass epoxy substrate, and a ceramic substrate or a metal substrate. FIG. 7 shows a structural example of the prior art.
In every case, a metal wiring layer 23 with a desired pattern applied thereto is formed on the surface of an insulating substrate 22 and a resist layer 24 is formed on part of the surface of the metal wiring layer 23 exposed so as to match the electrodes of electronic parts.
A method for manufacturing a coppered laminate resin substrate comprises forming a desired pattern by the electrochemical etching to make a metal wiring layer after bonding a copper foil to the surface of an insulating substrate 22 serving as a base. Then, resin serving as a resist layer 24 is printed by using a screen mask or the like and hardened.
Material examples of the insulating substrate 22 are a paper-based phenol resin impregnated substrate or a glass-textile-based epoxy resin impregnated substrate. The copper foil is prepared by electrolysis and rolling. The representative thickness is 0.2-1.6 mm for an insulating substrate 22, 0.009-0.05 mm for a metal wiring layer 23 and 0.005-0.05 mm for a resist layer 24.
In a method for manufacturing a metal substrate, aluminum or steel is used as an insulating base material 22, a copper layer is formed by sticking a copper foil on the surface or by plating after the insulating treatment of the surface, a metal wiring layer 23 subjected to a desired patterning by the electrochemical etching is formed and next a resist layer 24 is formed by the printing.
The representative thickness is 0.4-2.0 mm for an insulating base material 22 serving as the base, 0.01-0.2 mm for a metal wiring layer 23 and 0.005-0.05 mm for a resist layer 24.
A method for manufacturing a ceramic substrate comprises the steps of printing a paste onto a base material such as Al.sub.2 O.sub.3 in accordance with a desired pattern by using a screen mask which is prepared by kneading metal powder and glass powder with resin such as ethyl cellulose and a solvent such as terpineol as an insulating base material 22 serving as a base, evaporating or burning the resin and solvent by sintering at a temperature of 600-900.degree. C., securing the remaining metal powder and glass powder on the base material by fusion or sintering to thus form a metal wiring layer 23 and then forming a resist layer 24.
The representative thickness is typically 0.5-1.5 mm for a ceramic substrate serving as the insulating base material 22 and 0.005-0.05 mm for a metal wiring layer 23.
Since there is an insulating base material serving as the thick base for forming the metal wiring layer and a. resist layer, however, a conventional parts-packaging substrate as mentioned above problems that the manufacturing cost is high and is dependent on the price of an insulating base material serving as the base.
In addition, the connection to another substrate present an additional problem in that it is necessary to join a connector terminal as another part onto the parts-packaging substrate and then to connect the substrates to each other via the connector, increasing the total cost.
Thus, it is the object of the present invention. to provide a parts-packaging substrate which can be manufactured while omitting an insulating base material serving as the base or by using a simple substrate base and which needs no other parts for connection with other substrates, a method for manufacturing the same, and a method for manufacturing a module.